I'll have to run the numbers, but that is pretty awesome efficiency for your first AG brew. I think my first few were in the 55% range. I am consistently in the 70-80% range now. I would say that there are many other variables such as mash temp, technique, sparge, etc.

Reran my numbers. Ended up with 5.4 gallons @ 1.61 out of 11# of 2-row and 1# of Light Munich. I overcompensated on the gravity temperature correction.

Still, 78% is not a bad number for my first time doing a full all grain. I think I've squared away where I need to improve too; think I didn't let the first sparge sit long enough, so it didn't dissolve as much of the sugars as it could have.

Your numbers high or low don't matter as much as being able to hit that percent every time. My first AG % was crazy low, my second was high, mid 80s. Since then I've figured out my system and hit 75% + or - a % every time. This allows me to construct my recipes accordingly.

If you can hit that every time, that's awesome, but the big key is to find a consistent efficiency.

Hey, if I can squeeze a few extra percent points out and get an 80% efficiency off of my next batch, I'll be one happy camper.

I'll add that I have pretty ideal brewing water to start, to this batch I added 1/2 tsp of burton salts to help with the bittering. my tapwater is pretty good for most brewing, but i find that hoppy beers end up tasting one dimensional without a little extra assistance.

Next batch is going to be an english-stye or wheat beer without modifying the water to start, so I'm going to see if that helps overall efficiency.